Serial Dilutions Lab Report

Discuss what you did in this lab and what you will cover in the lab

Purpose: To learn about the international system of units (SI), to become familiar with common lab equipment and techniques, to gain proficiency in determining volume, mass, length, and temperature of a variety of items using common laboratory measurement devices, to learn to combine units to determine density and concentration, and to use laboratory equipment to create serial dilutions and determine the density and concentration of each dilution.

Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.

10 microliters of the sample is then added and the assay absorption is measured at 340nm. If absorbance was above 1.5, samples were diluted.

*****Safety Note: Please remove the safety goggles and gloves from the lab kit and wear

For each of the 3 acceptable trials, enter the precise volume in milliliters of sodium thiosulfate solution used in

Answer the lab questions for this week and summarize the lab experience using this form.

The proof (twice the % alcohol) starts at its maximum and goes down (as the alcohol evaporates). If we start with a high concentration of alcohol, we will get the azeotrope (95% alcohol, 5% water) for a while, then the concentration will decrease.

To conduct your laboratory exercises, use the Laboratory Manual located under Course Content. Read the introduction and the directions for each exercise/experiment carefully before completing the exercises/experiments and answering the questions.

3.6.3. 2, 4 – D (2, 4–Dichloro phenoxy acetic acid) stock solution (1mg/ml): 10.0mg of 2.4-D being weighed and dissolved completely in 1N NaOH to a final total volume

2. (5 pts) List and explain the names and affiliations of the various characters/stakeholders in this story – I’m looking for us to use the story to map out the complexities that are generally associated with solving public health puzzles – the stakeholders you list and explain here should apply to many of the cases we consider going forward.

The purpose of this lab was for the student to get involved with his or hers new lab kit as well as being able to know, identify and use each other tools provided in the kit. Another key learning aspect of this lab is to teach the student how to measure properly the many units in the SI system. I will be using laboratory dilutions, measurements, and weights to then calculate using algebraic formula.

During this lab period, the safety procedures that should be followed are wearing your lab coat, safety glasses, gloves and use proper tools for dissection.

Describe what you did in the experiment, and include methods and materials used. Do not

3. Use a sterile pipette to transfer 0.1 ml of each dilution on to a MacConkey agar plate.